Jolt ramming-machine.



E. H. MUMFORD, DECD.

R. s. MUMFORD. EXECUTRIX.

JOLT RAMMING MACHINE.

APPLICATION FILED SEPT. 19. 1914.

Patented Mar. 19, 1918.

ATTORNEYS WITNESSES E. H. MUMFORD, DECD.

R. s. MUMFORD. EXECUTRIX.

JOLT RAMMING MACHINE.

APPLICATION FILED SEPT. 19. 1914.

Patented ManlQ, 1918 2 SHEETSSHEET 2.

INVENTOR ATTORNEYS EDGAR H. MUMFORD, OF PLAINFIELD, NEW JERSEY;

ROSE SKEEL MUMFOBD JOLT RAMM'ING-MACHINE.

Specification of Letters Patent.

Patented Mar. 19, 1918.

Application filed September 19, 1914. Serial N 0. 862,473.

To all whom it may'concern:

a citizen of the United States, residing at Plainfield, .in thecounty ofUnion-and State of New Jersey, have invented certain new anduseful.Improvements in Jolt Hamming- Machines, of which the following isa specification.

This invention relates .to jolt ramming machines for ramming sand moldsand the like, andit has for its primary object the provision of animproved olt ramming machine in which shock to the foundry floor issubstantially eliminated. My invention also contemplates .an improvedform of hydraulic shock .jolt ramming machine. Still another objectresides in providing an improved apparatus whereby it is possible toefiectively and uniformly jolt ram sand molds V of considerablesuperficial area.

The foregoing, together with such other objects as hereinafterappearorare incident to my invention .1 attain bymeans of a construction which Ihave Iillustrated in preferredform in the accompanying drawings,wherein- Figure .1 is .a side elevation of :my improved machine with themold table .in section to more fully illustrate .the parts; Fig. 2 is asection through my improved means for actuating the mold-table; Figs?)and 4 are respectively a longitudinal and a transverse section of thepowermeans employed; Fig. .5 is a view showing a mold table actuated bymy improved devicein which, however, only one hydraulic element isemployed; Fig. 6 is an endelevation of a detail .of my invention, andFig. 7 is a sectional view taken on the line VII-VII of Fig. 1.

Briefly stated, my invention consists in imparting a jolting movement toa mold supportingmember-or table through the mediumof one or morehydraulic columns, that is, columns of liquid, acting against suchsupportingmemberor table. One embodiment of my invention is shown in theaccompanying drawings and will now be described.

Referring to .Fig. 1, it will be seen that I provide-an anvil 7 which ispreferably a heavy block ofcast metal, earned on beams 8 which areyielding or yieldinglyzsupported, or both, as for example, by thesprings 9. Bolted to the top of the anvil are two Be it known thatLEDGAR M-UMFORD,

pairs of cylinders 10 arranged symmetrically at four simultaneouscenters of percussion substantially at the corners of the anvil in theupper part of each of which a plunger 11 bearing against the lower faceof the mold table 12 is adapted to Work. When the table is in loweredposition, it rests upon the flanges '10 formed on the upper parts of thecylinders 10. Opening into the chamber A of each cylinder-is a pipe 14which leads to a pressure box 15. The invididual chambers of thepressure box are connected to a source of liquid supply, such as a tank,16,by means of the pipes 17 and manifold 18. The supply tank 16 islocated above thelevel of the cylinders so that the liquid has a gravityfeed into the chambers A, which chambers are thus kept filled so as toprovide what may be termed hydraulic columns which serve to actuate thetable, as will further appear.

Mounted in the pressure box 15, in individual communication with thepipes 14, are fourmovable members or .plungers 23 which are packed asindicated at 25, so as to prevent leakage (see Fig. 7). Adjacent to thepressure box and connected thereto by means of the four bars 19 is apneumatic ram 20 having a hammer 21 which is operated by fiuidvpressureor other power means, in any preferred manner.

The operation of the device (is as follows, assuming that the mold tableis in .the position indicated in Fig. 1: The hammer'21 is driven forwardto strike the plungers 23 a heavy blow, and these in turn act upon theliquid in the individual chambers of the pressure box, the pipes 14 andchambers A driving it forward, thereby suddenly raising the pressures ofthe hydraulic columns causing them to act upon and'lift the table with ajolt. The liquid in the pressure box escapes but very slightly into thetank 16 because of the needle valves 22, and, in case of overload on themold table, which would occasion excessive pressures, I provide safetyvalves 24 in the pipes 14. The blow on the plungers 23 transmittedthrough the hydraulic columns olts the table with an efiect on the sandanalogous to that obtained in the well known types of jolt rammerwherein the mold table and its associated parts are elevated and thenallowed to drop to impact upon an anvil. Each plunger 23 communicatespreferably with some individual pipe so that the jolting impulse istransmitted uniformly to all the jolting devices regardless of any lackof uniformity in loading at percussion points. In the ordinary type ofmachine the ramming is effected by arresting the movement of the fallingtable as distinguished from imparting an upwardly directed blow to astationary table. However, I have found by experience thatI am enabledto ram molds effectively and with greater rapidity with my improved typeof jolt ramming machine, and this with scarcely any perceptible shock tothe earth from the resiliently supported anvil, the principle being thatwhen an acceleration of a certain magnitude is given to the plungers 11,the resulting force acts and reacts equally upon the mold table and itsload and the resiliently supported anvil 7 whose momentary accelerationsare in inverse proportion to their masses. The shock on the foundryfloor, due to the deflection of the anvil, may be taken up in severalways. For example, the anvil may be so arranged as to be capable ofconsiderable range of movement upon its resilient support and this willreduce the shock to the floor in proportion to the time taken to stopit. On the other hand, the greater the mass of the anvil, the less willbe the momentary velocity thereof and the shock to the floor will beless on this account, regardless of the amplitude of movement. The massof the anvil, the mass of the hammer, and the force of the blowdelivered by the latter may be varied to suit' the character of the workto be done and the conditions of doing it.

Although other forms of power means may be employed to actuate theplungers 23, I prefer to use a pneumatic hammer having a long stroke soas to utilize the expansion of the air, thereby effecting an economy inair consumption.

It will be apparent that I can operate a mold table with a singlecolumn, but it Will also be seen that by the useof my invention I amenabled to successfully, uniformly, and efiectively jolt ram molds ofvery large dimensions, molds the superficial area of which would renderit impossible to ram them with the ordinary jolt ramming machine. Thiscan be done by providing a plurality of columns, the mold table; for theblow delivered to'the plungers 23 will be imparted through the differentcolumns uniformly to these percussion points under the table, with aresultant uniformity in the ramming. By transmitting the blow throughthe water columns, it

is possible to conveniently arrange the power means with reference tothe mold table, regardless of the size-of the latter or the number ofcolumns. V

The member 7 has been termed an anvil because it supports a cylinder orcylinders terminating at different points under 10, and the hydrauliccolumn reacts on the cylinder and the member 7 when-the ram is operated,and thus imparts a jolting movement or impulse to the table 12 throughthe piston or pistons 11. In this sense therefore the block 7 andits'associated parts is an anvil-like member.

The foregoing advantages together with those incident to'the substantialelimination of shock to the foundry floor, will be readily apparent tothose skilled in the art to which this invention pertains.

I claim v 1. A jolt ramming apparatus comprising in combination amold-supporting member, an hydraulic column arranged to act upon saidmember, and means for imparting a jolting impulse to the supportingmember through the medium of the hydraulic column. 7 I

2. A jolt ramming apparatus comprising in combination a mold-supportingmember,

a plurality of hydraulic columns arranged to act upon saidrmember, andmeans for imparting simultaneous jolting impulses to the supportingmember through the medium of the hydraulic columns.

3. A jolt ramming apparatus comprising in combination a mold-supportingmember, an anvil, an interposed hydraulic column, and means forimparting a jolting impulse to the supporting member through the mediumof the hydraulic column.

l. A jolt ramming apparatus comprising in combination a mold-supportingmember, a yieldingly supported anvil, an interposed hydraulic column,and means for imparting ajolting impulse to the supporting memberthrough the medium of the, hydraulic column.

5. A jolt ramming apparatus comprising in combination a mold-supportingmember, a plurality of hydraulic columns arranged to act upon saidmember, and a common means for imparting jolting impulses to thesupporting member through the medium of the hydraulic columns. f

6. A jolt ramming apparatus comprising in combination a mold-supportingmember, an hydraulic column arranged to act upon said member, and meansfor imparting a jolting impulse through the medium of the hydrauliccolumn, comprising a movable member act-, ing upon the hydraulic columnand adapted when moved to raise the pressure on the column. 4 r

7. A jolt ramming apparatus comprising in combination a mold-supportingmember, an hydraulic column arranged to act upon said member, means forimparting a jolting impulse to the supporting member'through to thesupporting member 7 the medium of the hydraulic column comthe pressureon the column, and a ram for delivering a blow to said movable member.

' a plurality of hydraulic columns arranged to act upon said member, amovable member acting upon each column to impart therethrough a joltingimpulse to the supporting member, and common means for simultaneouslydelivering a blow to each of said movable members.

9. A jolt ramming apparatus comprising in combination a mold-supportingmember, a plurality of hydraulic columns arranged to act upon saidmember, a movable member acting upon each column to impart therethrougha jolting impulse to the supporting member, and a ram for simultaneouslydelivering a blow to each of said movable members.

10. A jolt ramming apparatus comprising in combination a mold-supportingmember, an anvil, a plurality of interposed hydraulic columns arrangedto act upon said members, a movable member acting upon each column toimpart therethrough a jolting impulse to the supporting member, andcommon means for simultaneously delivering a blow to each of saidmovable memers.

11. A jolt ramming apparatus comprising in combination a mold-supportingmember, a yieldingly supported anvil, a plurality of interposedhydraulic columns arranged to act upon said members, a movable memberacting upon each column to impart therethrough a jolting impulse to thesupporting member, and common means for simultaneously delivering a blowto each of said movable members.

12. In jolt ramming apparatus, a plurality of hydraulic columns, and acommon means for simultaneously imparting jolting impulses thereto.

13. In jolt ramming apparatus, a plurality of hydraulic columns, and acommon means for imparting jolting impulses to each column independentlyof the other columns.

In testimony whereof I have hereunto signed my name in the presence ofthe two subscribed witnesses.

EDGAR H. MUMFORD.

Witnesses JENNIE H. GoLns'rnIN, LAURA E. SMITH.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents.

Washington, D. C.

